The shapes of saccadic eye movements tracking patterns have been used to aid the diagnosing of certain disease states, such as myasthenia gravis, multiple sclerosis and cerebellar tumors. However, some of these may been confounded by fatigue, lack of normalitive data, and instrumentation difficulties. We propose to gather normalitive data about the variations in the hyperfine structure of saccadic eye movements and to use this data gathered with the same instrumentation to study patients in a new laboratory. A specific hypothesis to be tested is that the presence of glissadic undershoot of the adducting eye and commitant glissadic overshoot of the abducting eye along with abduction nystagmus is not a sufficient test for internuclear opthalmoplegia nor is it a good early diagnostic for multiple sclerosis. We wish to identify the control signal variations the produce these glissades.